1. Spatial orientation of the ventricular muscle band: Physiologic contribution and surgical implications 
Francisco Torrent-Guasp, MDa, Manel Ballester, MDb, Gerald D. Buckberg, MDc, Francesc Carreras, MDd, Albert Flotats, MDd, Ignasi Carrió, MDd, Ana Ferreira, MDb, Louis E. Samuels, MDe, Jagat Narula, MDe 
The Journal of Thoracic and Cardiovascular Surgery 
Volume 122, Issue 2, Pages (August 2001)
DOI: /mtc
Copyright © 2001 American Association for Thoracic Surgery Terms and Conditions

2. Fig. 1
The consecutive stage of the unwinding of the ventricular myocardial band are shown. See Figure 2 (steps A-E) for schematic representation.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /mtc )
Copyright © 2001 American Association for Thoracic Surgery Terms and Conditions

3. Fig. 2
Schematic representation of the ventricular myocardial band (A-E) for consecutive stages of unwinding. The myocardial band can be divided into four segments (E): RV free wall(RFW, black), LV free wall (LFW, dark gray), descending segment (DS, white), and ascending segment (AS, light gray). The myocardial band extends between the pulmonary artery (PA) and the aorta (Ao). These segments spatially conform to two loops: the basal loop (from a to b ), constituted by RFW (black) and LFW (dark gray), and the apical loop (from b to c ) formed by the descending segment (DS, white) and the ascending segment (AS, light gray). The spatial configuration of both loops forms a helicoid as shown in Figure 3. Arrows indicate the cleavage plane that provide clues for unwinding the myocardial band. apm, Anterior papillary muscle; AS, ascending segment; Ao, aorta; DS, descending segment; LFW, left ventricular free wall; lt, left trigone of the aorta; PA, pulmonary artery; ppm, posterior papillary muscle; RFW, right ventricular free wall; rt, right trigone of the aorta.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /mtc )
Copyright © 2001 American Association for Thoracic Surgery Terms and Conditions

4. Fig. 3
Schematic representation of the spatial configuration of the ventricular myocardial band as a helicold. Abbreviations and shading as a Figure 2.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /mtc )
Copyright © 2001 American Association for Thoracic Surgery Terms and Conditions

5. Fig. 4
Proposed explanation of the late systolic upward motion of hte base of the ventricles. A, The outer shell formed by the basal loop has been unwound to display the descending and ascending segments of the band, which are seen shaded in B, C and D illustrate the way the descending and ascending segments behave during systole. In early systole the base of the heart is pulled toward the apex because of contraction of the descending segment(thick bundles shaded lightly); such a movement forces the ascending segment to adopt an “S” configuration in late systole. Contraction of the ascending segment (thick bundles in light gray) stiffens such a segment and results in upward movement of the base of the heart. The latter movement could be compared to the way contraction of the dorsal musculature of the snake elongates its body through stiffening of the muscles. Depicted in E is a scheme of the forced “S” configuration of the ascending segment (left), the contraction leads to a shortened “s” (middle), and the likely configuration it adopts in late systole (right). Contraction of the descending and ascending fibers also results in a rotational motion of the heart, as illustrated in the two intermediate figures, which depict such movement as seen from the apex.
The Journal of Thoracic and Cardiovascular Surgery  , DOI: ( /mtc )
Copyright © 2001 American Association for Thoracic Surgery Terms and Conditions